class ChatGroup:
    def __init__(self, groupname, userlist):
        self.groupname = groupname
        self.userlist = userlist

class User:
    def __init__(self, addr, socket):
        self.addr = addr
        self.socket = socket

class Message:
    def __init__(self, action, toUser, chatGroup, data):
        self.action = action
        self.toUser = toUser
        self.chatGroup = chatGroup
        self.data = data